unfortunately, this is as mini a f407vet board as i can find for now and one which is decently well build (and not too high priced). u'd only need to look at the monster number of pins on the headers, that's possibly as little area to put all that headers breaking out all the pins

that 25mhz oscillator is a ceramic resonator, the 32768 hz RTC oscillator beside it is a ceremic resonator as well correctionshttps://en.wikipedia.org/wiki/Ceramic_resonator
but i'd think that'd at least beat a simple RC oscillator in terms of frequency-voltage sensitivity
RC oscillators are possibly even more sensitive to voltage swings and temperature swings vs a ceramic resonator

ag123 wrote:that 25mhz oscillator is a ceramic resonator, the 32768 hz RTC oscillator beside it is a ceremic resonator as well correctionshttps://en.wikipedia.org/wiki/Ceramic_resonator
but i'd think that'd at least beat a simple RC oscillator in terms of frequency-voltage sensitivity
RC oscillators are possibly even more sensitive to voltage swings and temperature swings vs a ceramic resonator

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my goof NX5032GA seemed to be a smd crystal, rather than ceramic resonatorhttp://www.ndk.com/images/products/cata ... SU-2_e.pdf
it seemed the 'epson' 32768khz part is also an smd crystal just that i'm not sure what is the part number for it
i'd guess a little more research is needed about these smt crystals